In a semiconductor device manufacturing line, dimensional control of a circuit pattern is regarded as an indispensable technology for improvement of yield and control of quality. For the dimensional control, a CD-SEM (Critical-Dimension Scanning Electron Microscopy) is used which is a type of the charged particle beam device and applies an electron microscope which realizes high spatial resolution. The CD-SEM realizes a high spatial resolution with a low energy electron beam and can measure a lateral (in an in-plane direction of a circuit pattern) dimension of a circuit pattern with sub-nanometer accuracy.
Patent Literature 1 discloses an orthogonal electromagnetic field generator (hereinafter, also called E×B deflector or E×B type filter) which deflects electrons which are discharged from a sample to the outside of the axis of the electron beam without deflecting the electron beam which is discharged from an electron source. Patent Literature 1 also describes that another E×B deflector is provided to cancel out aberration generated by the E×B deflector. And, Patent Literature 2 discloses a scanning electron microscope which cancels out aberration generated when the beam is deflected by using the E×B deflector. Patent Literature 3 describes that a position-sensitive detector is arranged in an image surface of signal electrons to visualize (make an image of) signal electrons, and direction information obtained by arranging the position-sensitive detector on a diffraction plane of signal electrons is also reflected in the image.